JSDoc for top-level modules files

lib/internal/modules/helpers.js

@@ -37,7 +37,13 @@ let debug = require('internal/util/debuglog').debuglog('module', (fn) => {
   debug = fn;
 });
 
+/** @typedef {import('internal/modules/cjs/loader.js').Module} Module */
+
+/** @type {Set<string>} */
 let cjsConditions;
+/**
+ * Define the conditions that apply to the CommonJS loader.
+ */
 function initializeCjsConditions() {
   const userConditions = getOptionValue('--conditions');
   const noAddons = getOptionValue('--no-addons');
@@ -51,41 +57,63 @@ function initializeCjsConditions() {
   ]);
 }
 
+/**
+ * Get the conditions that apply to the CommonJS loader.
+ */
 function getCjsConditions() {
   if (cjsConditions === undefined) {
     initializeCjsConditions();
   }
   return cjsConditions;
 }
 
-function loadBuiltinModule(filename, request) {
-  if (!BuiltinModule.canBeRequiredByUsers(filename)) {
+/**
+ * Provide one of Node.js' public modules to user code.
+ * @param {string} id The identifier/specifier of the builtin module to load
+ * @param {string} request The module requiring or importing the builtin module
+ */
+function loadBuiltinModule(id, request) {
+  if (!BuiltinModule.canBeRequiredByUsers(id)) {
     return;
   }
-  const mod = BuiltinModule.map.get(filename);
+  /** @type {import('internal/bootstrap/realm.js').BuiltinModule} */
+  const mod = BuiltinModule.map.get(id);
   debug('load built-in module %s', request);
   // compileForPublicLoader() throws if canBeRequiredByUsers is false:
   mod.compileForPublicLoader();
   return mod;
 }
 
+/** @type {Module} */
 let $Module = null;
+/**
+ * Import the Module class on first use.
+ */
 function lazyModule() {
   $Module = $Module || require('internal/modules/cjs/loader').Module;
   return $Module;
 }
 
-// Invoke with makeRequireFunction(module) where |module| is the Module object
-// to use as the context for the require() function.
-// Use redirects to set up a mapping from a policy and restrict dependencies
+/**
+ * Invoke with `makeRequireFunction(module)` where `module` is the `Module` object to use as the context for the
+ * `require()` function.
+ * Use redirects to set up a mapping from a policy and restrict dependencies.
+ */
 const urlToFileCache = new SafeMap();
+/**
+ * Create the module-scoped `require` function to pass into CommonJS modules.
+ * @param {Module} mod The module to create the `require` function for.
+ * @param {ReturnType<import('internal/policy/manifest.js').Manifest['getDependencyMapper']>} redirects
+ * @typedef {(specifier: string) => unknown} RequireFunction
+ */
 function makeRequireFunction(mod, redirects) {
   // lazy due to cycle
   const Module = lazyModule();
   if (mod instanceof Module !== true) {
     throw new ERR_INVALID_ARG_TYPE('mod', 'Module', mod);
   }
 
+  /** @type {RequireFunction} */
   let require;
   if (redirects) {
     const id = mod.filename || mod.id;
@@ -131,13 +159,22 @@ function makeRequireFunction(mod, redirects) {
     };
   }
 
+  /**
+   * The `resolve` method that gets attached to module-scope `require`.
+   * @param {string} request
+   * @param {Parameters<Module['_resolveFilename']>[3]} options
+   */
   function resolve(request, options) {
     validateString(request, 'request');
     return Module._resolveFilename(request, mod, false, options);
   }
 
   require.resolve = resolve;
 
+  /**
+   * The `paths` method that gets attached to module-scope `require`.
+   * @param {string} request
+   */
   function paths(request) {
     validateString(request, 'request');
     return Module._resolveLookupPaths(request, mod);
@@ -159,6 +196,7 @@ function makeRequireFunction(mod, redirects) {
  * Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)
  * because the buffer-to-string conversion in `fs.readFileSync()`
  * translates it to FEFF, the UTF-16 BOM.
+ * @param {string} content
  */
 function stripBOM(content) {
   if (StringPrototypeCharCodeAt(content) === 0xFEFF) {
@@ -167,6 +205,11 @@ function stripBOM(content) {
   return content;
 }
 
+/**
+ * Add built-in modules to a global or REPL scope object.
+ * @param {object} object The object such as `globalThis` to add the built-in modules to.
+ * @param {string} dummyModuleName The label representing the set of built-in modules to add.
+ */
 function addBuiltinLibsToObject(object, dummyModuleName) {
   // Make built-in modules available directly (loaded lazily).
   const Module = require('internal/modules/cjs/loader').Module;
@@ -227,9 +270,8 @@ function addBuiltinLibsToObject(object, dummyModuleName) {
 }
 
 /**
- *
+ * If a referrer is an URL instance or absolute path, convert it into an URL string.
  * @param {string | URL} referrer
- * @returns {string}
  */
 function normalizeReferrerURL(referrer) {
   if (typeof referrer === 'string' && path.isAbsolute(referrer)) {
@@ -238,7 +280,10 @@ function normalizeReferrerURL(referrer) {
   return new URL(referrer).href;
 }
 
-// For error messages only - used to check if ESM syntax is in use.
+/**
+ * For error messages only, check if ESM syntax is in use.
+ * @param {string} code
+ */
 function hasEsmSyntax(code) {
   debug('Checking for ESM syntax');
   const parser = require('internal/deps/acorn/acorn/dist/acorn').Parser;

lib/internal/modules/run_main.js

@@ -7,6 +7,10 @@ const {
 const { getOptionValue } = require('internal/options');
 const path = require('path');
 
+/**
+ * Get the absolute path to the main entry point.
+ * @param {string} main Entry point path
+ */
 function resolveMainPath(main) {
   // Note extension resolution for the main entry point can be deprecated in a
   // future major.
@@ -21,6 +25,10 @@ function resolveMainPath(main) {
   return mainPath;
 }
 
+/**
+ * Determine whether the main entry point should be loaded through the ESM Loader.
+ * @param {string} mainPath Absolute path to the main entry point
+ */
 function shouldUseESMLoader(mainPath) {
   /**
    * @type {string[]} userLoaders A list of custom loaders registered by the user
@@ -41,6 +49,10 @@ function shouldUseESMLoader(mainPath) {
   return pkg && pkg.data.type === 'module';
 }
 
+/**
+ * Run the main entry point through the ESM Loader.
+ * @param {string} mainPath Absolute path to the main entry point
+ */
 function runMainESM(mainPath) {
   const { loadESM } = require('internal/process/esm_loader');
   const { pathToFileURL } = require('internal/url');
@@ -52,6 +64,10 @@ function runMainESM(mainPath) {
   }));
 }
 
+/**
+ * Handle process exit events around the main entry point promise.
+ * @param {Promise} promise Main entry point promise
+ */
 async function handleMainPromise(promise) {
   const {
     handleProcessExit,
@@ -64,9 +80,12 @@ async function handleMainPromise(promise) {
   }
 }
 
-// For backwards compatibility, we have to run a bunch of
-// monkey-patchable code that belongs to the CJS loader (exposed by
-// `require('module')`) even when the entry point is ESM.
+/**
+ * Parse the CLI main entry point string and run it.
+ * For backwards compatibility, we have to run a bunch of monkey-patchable code that belongs to the CJS loader (exposed
+ * by `require('module')`) even when the entry point is ESM.
+ * @param {string} main CLI main entry point string
+ */
 function executeUserEntryPoint(main = process.argv[1]) {
   const resolvedMain = resolveMainPath(main);
   const useESMLoader = shouldUseESMLoader(resolvedMain);